A cylinder head gasket sandwiched between a cylinder block and a cylinder head in which a combustion chamber, an oil passage, a water passage, and a bolt insertion passage are formed and provided with a combustion chamber hole drilled at a position of the combustion chamber and an oil hole drilled at a position of the oil passage has conventionally been known.
In such cylinder gaskets, a load is concentrated at a periphery of the combustion chamber in order to seal a combustion gas from the combustion chamber hole, and specifically, those with an increased plate thickness at the periphery of the combustion chamber hole or with beads surrounding the combustion chamber hole formed are known (Patent Documents 1 to 7).